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their normal weight counterparts (
Chen et al., 2006; Shang et al., 2010
)
.
Mak et al. (2010)
found that both overweight and obese adolescents per-
formed poorly on push-up, sit-up, and endurance running tests but not
on the sit-and-reach tests, which mainly assessed flexibility. This result is
similar to a later study conducted in Oaxaca, Mexico, where overweight
and obese adolescents were found to have less muscular strength and endur-
ance
(
Malina, Reyes, Tan, & Little, 2011
).
Compared to other components of PF, cardiorespiratory fitness has often
been shown to be more important in evaluating a child's overall fitness level
(
Nassis et al., 2005
)
. Therefore, most researchers have focused on and used
only the cardiorespiratory fitness component when assessing an individual's
PF. Overall, many studies have reported that a high cardiorespiratory fitness
level was significantly associated with lower total or central body fatness
among children and adolescents
(
Ara, Moreno, Leiva, Gutin, & Casaj´ s,
2007; Ortega et al., 2007
), not only for normal weight individuals but also
for overweight and obese children (
Nassis et al., 2005
)
. In addition, several
studies also showed that cardiorespiratory fitness levels achieved during child-
hood and adolescence can help predict total and central body fatness in adult-
Based on the available evidence, it can be concluded that low PF, par-
ticularly a low cardiorespiratory fitness level, is significantly associated with
higher total or central body fatness among children and adolescents. How-
ever, little is known about the relationships between other elements of PF
and overweight and obesity development in children and adolescents.
Hence, more quality studies that involve different elements of PF should
be conducted to further investigate the role of PF in body fatness gain in
these young populations.
6.3. Energy cost of PA and obesity
Obese children and adolescents have higher body weights and greater FFM
and consequently a higher total daily energy expenditure (TDEE), BMR,
and AEE than nonobese subjects (
Treuth et al., 1998
)
. The higher TDEE
could also be explained by the higher body weight in overweight adoles-
cents. Obese children require extra energy to move around due to their
higher body mass. However, previous studies have shown that obese chil-
dren usually spend less time in PA and more time involved in sedentary
activities compared to their age-matched counterparts
(
Chou & Pei,
2010; Ramachandran et al., 2002
). This observation raises the question of
